An On-Line Algorithm for Edge-Ranking of Trees
نویسندگان
چکیده
An edge-ranking of a graph G is a labeling of the edges of G with positive integers such that every path between two edges with the same label γ contains an edge with label λ > γ. In the on-line edge-ranking model the edges e1, e2 . . . , em arrive one at a time in any order, where m is the number of edges in the graph. Only the partial information in the induced subgraph G[{e1, e2, . . . , ei}] is available when the algorithm must choose a rank for ei. In this paper, we present an on-line algorithm for ranking the edges of a tree in time O(n), where n is the number of vertices in the tree.
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